The graph you’re referring to illustrates the percentage of people in different age groups attending music concerts in a particular city between 2010 and 2015.
Overall, the youngest age group demonstrated the highest interest in music concerts, while the oldest age group (55-64 and over 75) had lower participation rates.
At 40% in 2010, the percentage of the youngest age group grew to 55% in 2011, and then continued to rise to 70% in 2015. The figure for those from 25 to 44 years old, despite having a higher starting point(2), dipped to 40%, before recovering to its initial value in 2012 and rising steadily to about 53% in 2015.
Regarding the 45-54 year-olds and the over-75 year-olds, from 2010 to 2011, the figure for the former dropped from 40% to 32%, while that of the latter doubled to 20%. However, by 2012, these figures had both fallen to 30% and 10%, before rising again to nearly 50% and 20% respectively. Meanwhile, there was a slight rise in the percentage of 55 to 64 year-old concert goers from 2010 to 2013, followed by a gradual decrease to around 23% by 2015.